#include <stdio.h>
#include <stdlib.h> 
#include <time.h>
int main(void){
	int i,j,flag;
	srand((unsigned) time (NULL));
again:	for (i=0;i<6;i++){
		j=rand()%26+65;
		printf("%c",j);
	}
	scanf("%d",&flag);
	if (flag!=0)
		goto again;
	return 0;
}
